A mobile device requires the establishment of a radio access bearer in order to communicate with the wireless network infrastructure. Furthermore, some devices allow the establishment of multiple radio access bearers for communication. In one instance, multiple radio access bearers can be dependent on the device requiring multiple packet data protocol (PDP) contexts. Thus, for example, a device may have a proprietary PDP context for the manufacturer of the device, a general wireless application protocol (WAP) context for browsing, a multi-media messaging service (MMS) PDP context for MMS applications, a streaming media PDP context for streaming media applications, among others. As will be appreciated, a PDP context is a term that is generally referred to in the third generation partnership project (3GPP) and more generally, the term “tunnel” is used herein to refer to a data connection to a particular network.
Various networks or network conditions may determine how many tunnels can be opened between a device and the network. The number of tunnels that can simultaneously be open on the device is called a “watermark”.
If a watermark on the device is less than the number of tunnels that the device wishes to open, a tunnel prioritization scheme may be employed to determine which tunnels have access to the radio resources. One tunnel prioritization scheme is described with reference to FIGS. 2-4 of U.S. patent application Ser. No. 12/413,418, the contents of which are incorporated herein by reference. As described in the '418 reference, priorities can be provided based on various factors including whether or not a application or service is “in focus”, meaning that the application is in the foreground. Thus, for example, if the user of the mobile device is browsing the Internet, a browser application may be displayed on the screen of the mobile device and that application may be considered to be “in focus”. The WAP tunnel associated with the browser may be considered to be the focused tunnel and thus might be given the highest priority to ensure a good user experience.
In cases where the focused tunnel is idle, however, and if a limited number of tunnels are available, the reservation of resources by the focused tunnel starves other services of tunnel access.